Rotatable suspension hook for work conveyors



1955 J. L. RUSH 2, 9

Rom'mw susmuszon aoox FOR WORK couvvofis Filed N06. 16, 1953 JfFF/E LEE 205/1.

INVENTOR.

United States Patent ROTATABLE SUSPENSION HOOK FOR WORK CONVEYORS Jefiie Lee Rush, Kansas City, Mo.

Application November 16, 1953, Serial No. 392,218

Claims. (Cl. 198-177) This invention relates to rotatable suspension hooks for work conveyors.

It is common practice in factories producing large items which are conveyed from place to place to use conveyors having suspension hooks thereon, by means of which the work pieces can be carried from station to station. In some cases such conveyors and hooks are employed for the purpose of carrying the work through a zone in which the work piece is to be treated, as for the purpose of painting or coating the work piece. Thus it is common practice to provide conveyors for carrying heavy work pieces to and through painting stations at which the work pieces are immersed or sprayed or brushed, and from which they are carried to a drying room to cause rapid drying of the paint so that the work pieces may be further processed or may be packed or otherwise treated ready for shipment.

Suspension hooks for conveyors of this character are preferably rotatable so that the work may be turned as it is carried by the conveyor for access of different faces or portions thereof to a paint spray and for convenience of painting or treatment. At the same time it is desirable that the rotation proceed through predetermined arcs or angles, and that the work be normally held in fixed rotative position for the performance of a treating operation thereon. These two conditions require freedom of the suspension hook to rotate and avoidance of adhesion of the parts or sticking thereof due to adherence of paint or other treating material upon the parts of the hook.

Prior work holders have quite commonly been subject to sticking thereof after use for only a short period of time under normal factory conditions. Various efforts have been made to provide a hook in which the parts are shielded against the access of paint to the relatively rotatable members but such efforts have not been successsful and have been subject to failure in the accomplishment of the intended purpose of avoiding sticking due to the paint or coating or have been objectionable from the standpoint of weight or of cost or of some other factor.

It is the primary object of this invention to provide a novel, simple and inexpensive rotatable suspension hook for work conveyors with means by which paint adhering thereto may readily, quickly and simply be removed therefrom during the use of the suspension hook.

Another object is to provide a device of this character having relatively rotatable parts of which one is flexible and fits around the other and serves, when flexed, to scrape from the other paint which may have accumulated thereon. I

A further object is to provide a device of this character having a plurality of angular or rotative dwell stations and resilient means for serving to maintain said parts at said dwell station, but flexible to traverse an associated part as the hook is rotated from one dwell station to another.

Another object is to provide a device of this character comprising a head having a socket and rotatably receiving a hook, wherein said socket and a portion of said hook have cooperative cam faces adapted, upon rotation of the hook relative to the head, to cause longitudinal movement of the hook, and wherein a flexible washer is carried by said head and encircles the shank of said hook with a snug fit and normally bears against a shoulder on said shank so that said shoulder causes flexing of said disk when said shank'moves longitudinally, said disk having a normal snug fit around the shank of the hook to limit the access of liquid therepast and around the shank and into the socket of the head.

A further object is to provide a device of this character having a head formed of two parts, whose parting plane intersects a socket located within the head and adapted to receive the shank and head portion of a hook and a flexible washer encircling the hook shank adjacent the mouth of the socket and spaced from the head on the shank of the hook.

Other objects will be apparent from the following specification.

Fig. 1 is a side view of a conveyor showing two of my improved suspension. hooks mounted thereon;

Fig. 2 is a sectional view taken on line 22 of Fig. 5; and illustrating the hook in one rotative position;

Fig. 3 is a view similar to Fig. 2 but illustrating the hook in a different rotative position and also in a longitudinally displaced position;

Fig. 4 is an inner face view of one section of the hookreceiving socket member;

Fig. 5 is a transverse sectional view taken on line 55 of Fig. 2; and

Fig. 6 is a fragmentary enlarged perspective detail view of the head on the shank of a hook member used in my device.

Referring to the drawing which illustrates the preferred embodiment of the invention, the numeral 10 designates a guide member or track which is mounted overhead by suitable supports (not shown) and which is strong and rigid to enable it to sustain the weight of a number of work pieces passing therealong. The guide 10 preferably is a metal structural member, such as metal channel or I-beam, and preferably will have a lower horizontal portion or flange 12. This guide 12 extends in an endless path extending past all the work stations at which work mounted on the conveyor is to be processed or treated. Thus, if the device is used as a conveyor for work to be painted, the member 10 would extend from a loading position to the painting station, a drying station or oven, a discharging station and back to the loading station.

A plurality of work carriers 14 are mounted to traverse the guide 10 in spaced relation to one another, each of these carriers mounting a roller 16 at its upper end which bears upon and rolls along the flange 12 of the guide 10. The carrier 14 is suspended from the roller and projects below the guide and has a towing connection at a link 18 with a towing member 20, such as a chain or a cable. The chain or cable is preferably located slightly spaced below the guide 10 and is associated with drive means (not shown) for shifting the same endwise and causing propulsion of the carriers 14.

The lower end of each carrier member 14 has connected thereto, and preferably pivoted at 22, a socket member 24. The socket member 24 is preferably vertically elongated and is vertically split or divided into sub stantially similar parts 26. The parting plane between the parts 26 is preferably transverse of the pivot pin-receiving opening 28 so that said opening is formed in each of said parts 26. The parts 26 are secured together by a bolt or screw 30 so as to be readily separable. Means to assure register of the two parts 26 is provided and such means may take the form best illustrated in Fig. 5, wherein ribs 32 project from one member 26 and seat in grooves or offset portions 34 formed in the other member'26 at the parting plane or face thereof. As here shown the ribs andoffsets are located at the margin of the parting plane or faces of the members, but this arrangement is illustrative and is not intended to be limiting, as registration means can be located wherever desired and may take any form found suitable.

The member 24 has a recess formed in its lower-end portion substantially concentric thereof and with its axis substantially coincident with the longitudinal axis of the socket member 24. The shape of this recess is best illustrated in Fig. 4 and comprises a mouth portion 36 of tapered shape defined by inwardly converging lip portions 39 of the member 24 at its mouth. From the large diameter inner end of the tapered socket portion 36, said socket tapers reversely at 38 in frusto conical form to a substantially cylindrical reduced portion 40. An enlarged inner chamber 42 communicates with the reduced portion 40. The shoulder 44 formed at the junction of the bore portions 40 and 42 is of undulating or cam form, for purposes to be described. The sockets of the two members 26 are similar and hence, when said members 26 are secured together in registration, the various parts of the socket will be in register and a continuous circular cavity is produced in the socket member.

A suspension hook 46 of any desired configuration has a shank portion 48 having an enlarged head 50 at its end and a reduced neck portion 52 intermediate its length. The neck portion 52 is of a diameter to fit snugly but rotatably in the reduced socket portion 40, and the head 50 fits with clearance within the inner chamber 42 of the socket member 24. The lower or inner end surface of the head 50 has an undulating or cam contour at 54 complementary to the cam contour 44 or shoulder of the socket member 24. The longitudinal dimension of the head 50 will be such that it has free clearance within the socket chamber 42 in all rotative positions, that is, its major longitudinal dimension at the widest camforming portion will be less than the smallest longitudinal dimension of the socket chamber 42 as determined at the crests of the cam edges or shoulders 44 thereof. The shoulder 56, which is formed between the neck 52 and the shank portion 48 of the hook, will lie in a plane substantially at the junction of the socket parts 36 and 38 when the head 50 lies in fixedly oriented position as determined by the cam contours 44 and 54 of the socket and head.

A metal disk 58, preferably formed of steel or of other material possessing resilience and a property of returning to normal shape after distortion, has a central aperture which fits snugly around the reduced neck 52 of the hook shank. The outer diameter of the disk 58 is slight ly less than the diameter of the socket at the junction of the socket portions 36, 38. In order to permit the application of the disk 58 to the hook, the head 50 on the hook shank may be formed separately in the nature of a ring or collar and may be mounted on the shank after the disk 58 has been applied, and may be anchored in place by a set screw, by screw threads, by welding or by any other means found suitable. The arrangement of the parts will preferably be such in the normal relation thereof, as illustrated in Fig. 2, that the shoulder 56 will lie adjacent to the outer face of the disk 58 when the disk 58 is fiat and unflexed.

In the use of this device, a work piece will be suspended from the hook 46 in the usual manner and will be carried from place to place, or station to station, from a loading point to a delivery point, in the manner well understood in the art. The rotative position of the work piece and of the suspension hook will be substantially constant under all normal conditions because of the interfitting of the cam surfaces 54 and 44 of the hook head 50 and the socket member 24. This insures that the work will reach and pass through the various stations in proper relation or rotative position, so as to avoid interference with of the socket member 24 in operative position.

machinery or building parts which the work piece passes and -to avoid swive1ing-orrotation thereof if it is touched accidentally. At the sametime the work piece may be intentionally rotated through a predetermined angle and will maintain the new rotative position thereafter as long as that new position is normal to the contour of the cams or position controlling surfaces 54 and 44.

The operation of rotating the work piece and its suspensionhook proceeds against the resistance to rotation afforded by the cam surfaces 54 and 44, and also the resistance provided by the resilient disk 58. Thus as the hook shank rotates from the position shown in Fig. 2 to the, position shown in Fig. 3, in which latter position the crests or crowns of the cams or positioning means engage, the hook shank is lifted bodily along with the work piece carried thereby and the shoulder 56 of the hook shank presses upwardly against the central portion of the disk 58. The outer diameter of the disk 58 being substantially equal to the diameter between the socket parts 36, 38, that is, the maximum diameter of the socket, the outer margin of the disk 58 cannot move with the hook shank. Consequently, the disk is flexed to substantially conical form, as illustrated in Fig. 3, when the cam crests are in engagement. The disk 58 serves as a barrier to prevent the access of paint, dirt and other coating materials or liquids from entering the socket of the member 24 and from reaching the inner socket parts 40 and 42 and the portions of the suspension hook which are received therein. For this purpose it is desirable normally that the disk 58 bear firmly against the shoulder 56 and, possibly, that the disk 58 be fixed slightly out of flat condition to insure a continuous circumferential contact with the shoulder 56. Consequently, access of paint and like coating materials to which the suspension member is subjected during painting or other treatment of the work carried by the conveyor, will normally be limited to the hook-shaped portion 48, the plate or disk 58, and the outer portion 36 only of the socket member. The paint, where used, or other coating material may have a tendency, however, to cause a bond or adhesion between the shank 48 and the disk 58, which tends to resist rotation of the hook, particularly if permitted to accumulate in multiple thickness or layers as would inevitably occur under normal factory or operating con ditions where each suspension hook would be subjected repeatedly to the paint as it carried successive work pieces to the paint station. Such adhesion or sticking of the paint is prevented by the present construction because the bond is broken each time that the hook is rotated. Thus, assuming that the hook shank is rotated at least once during each sequence of operation upon a work piece traveling from a pick-up station to a delivery station, it is apparent that any bond which tends to be formed is broken before it becomes too strong.

The flexing of the disk 58, which occurs in the socalled oil can fashion, entails such a change in the shape of the disk and proceeds with a snap action so that any coating material adhering thereto is released and broken up incident to rotation of the suspension hook 46.

In the event of wear requiring replacement of the disk 58 or in event of seepage of paint past the disk 58 by capillary action or otherwise, the device can readily be disassembled for reconditioning or for repair by release of the securing member 30 which holds the two halves 26 The socket member 24 will preferably be removed from the carrier 14 for this purpose but removal of the socket member is not necessary in all instances, particularly in the event there is any loose play at the pivot between the carrier 14 and the socket member 24 suflicient to facilitate separation of the parts 26 to swing the parts relative to each other and to release the suspension hook. Thus the device can be readily and rapidly repaired and manipulated to meet all operating conditions and to avoid extensive down time of the conveyor in the event repairs are required. The arrangement of the parts which permits their rapid assembly and disassembly is also important from the standpoint of holding at a minimum the initial cost of the mechanism, the cost of its assembly, and from the standpoint of making possible the use of cast or molded parts for the socket without the requirement of extensive machining.

While the preferred embodiment of the invention has been illustrated and described, it will be understood that changes in the construction may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, and in apertured resilient disc marginally anchored in said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket said shank having a shoulder engaging the outer surface of said disc.

2. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, and a resilient apertured disc marginally anchored in said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, said shank having a shoulder engaging the outer surface of said disc, said socket member being formed in two parts, the axis of said socket substantially coinciding with the parting plane of said parts, and means releasably securing said parts together.

3. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, and an apertured disc carried by said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, said socket member being formed of two parts each defining a part of said socket, said outer socket portion including a portion of maximum cross-sectional size spaced from said reduced portion and from its month, said disc seating snugly in said outer socket portion of maximum size, and means detachably connecting said parts.

4. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, an apertured resilient disc marginally anchored at said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, said shank having a shoulder abutting said disc, and means responsive to relative rotation of said socket member and hook for relatively shifting the same longitudinally.

5. A rotatable suspension hook for work conv yors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, an apertured resilient disc anchored by said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, said shank having an abutment engageable with said disc, and cam means between said head and socket for longitudinally shifting said hook relative to said socket member upon relative rotation thereof to flex said disc.

6. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, an apertured disc carried by said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, and a shoulder on said shank engaging said disc to distort said disc incident to longitudinal inward movement of said hook in said socket.

7. A rotatable suspension hook for work conveyors, comprising a socket member having a socket open at its bottom and including a reduced portion intermediate its length and separating inner and outer socket portions, a hook having a shank rotatable in said reduced portion and a head fitting in said inner socket portion, an apertured disc carried by said outer socket portion and encircling said shank to prevent entry of foreign matter into said socket, cam means associated with said head and socket to cause longitudinal movement of said hook incident to rotation thereof relative to said socket memher, and an abutment on said hook shank engageable with said disc to distort said disc upon longitudinal movement of said hook.

8. A rotatable work-suspending device, comprising a work-suspending member having a shank and an enlarged configured head defining a contoured shoulder, a socketed member having an inner configured chamber receiving said head and a reduced portion journaling said shank and spaced from the mouth of said socket, and an apertured disc encircling said shank and anchored in said socket spaced below said shank journaling socket portion, said shank having an abutment engaging the outer surface of said disc, the configured portion of said shoulder defining a support for the contoured shoulder of said head.

9. A rotatable work-suspending device, comprising a work-suspending member and a socketed member, said socketed member having a socket including an enlarged inner portion defining a shoulder, said work-suspending member extending into said socket and including an enlarged head bearing on said shoulder, the engaging surfaces or" said head and shoulder being non-planar, and a resilient apertured disc snugly encircling said work-suspending member and marginally anchored in said socket spaced from said head, said Work-suspending member having an abutment engageable with said disc to flex the same upon rotation of said work-suspending member relative to said socketed member.

10. A rotatable work-suspending device, comprising a work-suspending member having an enlarged head and an abutment spaced below said head, a resilient apertured disc encircling said member adjacent to and above said abutment, and a carrier having a cavity open at its lower end and including an enlarged upper head receiving portion, said disc being marginally anchored in said carrier cavity, and cam means for longitudinally displacing said work-suspending member in said carrier upon rotation thereof relative to said carrier whereby said disc is flexed.

References Cited in the file of this patent UNITED STATES PATENTS 

